Most Americans with a chronic illness say they would join a clinical trial if given the chance. Few are ever asked. In national polling of more than 2,000 adults conducted this year, 71 percent of patients with chronic conditions said they would be likely to participate in a trial if offered the opportunity, while two-thirds said their health care provider had never discussed clinical trials with them at all. The figures appear in national polling of patients with chronic conditions and were highlighted in reporting from KFF Health News examining why the gap persists.
The most widely cited measure of how rarely patients are invited is older. A federal survey brief using data collected in 2020 found that just 9 percent of adults reported ever being invited to participate in a clinical trial. That collection date should not be glossed over. It is a dated estimate rather than a current census, and no equivalent national measurement has replaced it.
The Referral Breaks Down Before the Patient Ever Sees a Trial
Physicians are not the obstacle people assume. In a survey of primary care physicians conducted this spring among just over 500 respondents and sponsored by the Patient Advocate Foundation, 86 percent said they were somewhat or very likely to refer a patient to a trial. Only 37 percent had ever actually done so.
The distance between intention and action is logistical. Mark Fleury, policy principal for emerging science at the American Cancer Society Cancer Action Network, described the process a community oncologist would face: search a registry, enter the patient's characteristics, review candidate studies, and call each site to confirm enrollment is still open. That is unpaid work layered onto an already compressed appointment. And as Fleury noted, a successful referral often means the physician loses the patient to another institution.
When trials did come up in those conversations, it was usually because the patient asked, because standard treatment was not working, or because the disease was progressing. Trials are being raised as a late option rather than presented early.
Alan Balch, executive board chair at the Patient Advocate Foundation, told KFF Health News that "every touchpoint is an opportunity for access and affordability to be a problem." His point was that signing people up is only the first hurdle, and that keeping them enrolled is a separate one.
Geography Decides More Than Motivation Does
Much of the clinical research in the United States is conducted at large academic medical centers, most of them in urban areas. Patients who do not live near one, or who are not already treated there, face a steeper path, because participation generally requires periodic in-person visits for blood draws, imaging, or assessments.
A 2019 study that examined 8,893 cancer patients found that more than half, 55.6 percent, had no available trial for their cancer type and stage at the facility where they were being treated. Another 21.5 percent were ineligible for a trial that did exist there. Taken together, that is roughly three-quarters of patients screened out before any personal decision was made.
The consequence runs in both directions. Up to 86 percent of clinical trials fail to meet their recruitment targets within the planned time frame, by one estimate cited in the reporting. Slow enrollment delays the evidence regulators need to evaluate new drugs and devices.
Decentralized trials, which let participants complete some tasks at home or at a local center, could widen the pool. Balch described the approach as not yet common, but said broader use would open participation to more patients and to more representative groups of patients.
The Costs That Sink Participation Are Rarely the Medical Ones
Trial sponsors pay for costs stemming directly from the study, including the investigational drug or device. Under the Affordable Care Act, most commercial plans must cover routine patient costs associated with an approved trial, and Medicare and Medicaid carry similar requirements.
Coverage is not the same as free. Participants still owe deductibles, copays, and coinsurance for routine care received during a trial. The ACA does not require plans to offer out-of-network benefits, so a trial run by a provider outside someone's network may not be covered at all.
Then come the expenses no insurer touches. Travel to the site, parking, lodging, childcare, and unpaid time away from work accumulate across months of study visits. For a family already managing a serious illness, those costs can decide participation more often than any clinical consideration.
Federal rules currently deter some sponsors from reimbursing those expenses. The Department of Health and Human Services opened a request for information as part of a broader clinical research initiative asking whether to change that. A bill pending in Congress, the Clinical Trial Modernization Act, would let sponsors cover participants' deductibles and copays along with travel and childcare, and would exclude up to $2,000 in trial-related support from federal taxes so participants do not lose eligibility for Medicaid or other income-based programs. Nearly 200 patient advocacy and public health groups wrote to the bill's Senate sponsors urging passage. Neither the rule change nor the bill has been enacted.
Practical Routes for Patients Who Want to Enroll
The federal registry at ClinicalTrials.gov is the most comprehensive listing and is searchable by condition and location. Disease-specific organizations also help, including the American Cancer Society, which runs a clinical trial matching service, along with the Arthritis Foundation and the National Multiple Sclerosis Society.
Patients treated at a hospital running a trial are generally best positioned to enroll, because most recruitment happens at the site itself. Asking a treating physician or the facility directly whether any studies are open is a reasonable first step.
Anyone who identifies a promising trial should contact the recruiters directly and ask about eligibility, insurance coverage, and whether the sponsor reimburses travel, lodging, or other incidental costs. Some sponsors do without advertising it. Nobody should leave established treatment for an experimental one without discussing it with a qualified clinician.
Key Questions Answered
Where does the 9 percent figure come from? A federal survey brief using data collected in 2020, in which 9 percent of adults reported ever being invited to participate in a clinical trial. It is a dated estimate, not a current national count.
Do patients actually want to participate? Polling of more than 2,000 adults this year found 71 percent of people with chronic conditions would likely participate if given the chance, while two-thirds said a provider had never discussed trials with them.
Why do doctors rarely refer patients? Finding an eligible trial requires searching registries, matching patient characteristics, and calling sites to confirm openings. In a survey conducted this spring, 86 percent of primary care physicians said they would refer, but only 37 percent ever had.
What is the biggest structural barrier? Location. In a 2019 study of 8,893 cancer patients, 55.6 percent had no trial available for their cancer type and stage where they were treated, and another 21.5 percent were ineligible.
Does insurance cover trial participation? Most plans must cover routine patient costs, but participants still owe deductibles, copays, and coinsurance, and out-of-network trials may not be covered.
What costs are not covered? Travel, parking, lodging, childcare, and lost wages. These are often the deciding factor, and current federal rules deter some sponsors from reimbursing them.
How can someone find a trial? Search ClinicalTrials.gov, ask a treating physician or hospital whether studies are open, and contact disease-specific advocacy organizations that offer matching services.
